Help me troubleshoot my frag tank!

[Drummerguydw]

Getting frustrated, how real is “sps like mature tanks”. I have a bare bottom frag tank that was setup for sps.

Having a hard time keeping my acropora happy, I’ve only lost one coral but I can notice some bleaching and lack of polyp extension and lack of growth on the others

Salinity: 35 ppm
Alk:9
Ca:460
Mag:1400
Po4:0.06 ppm
N03:7

All parameters are controlled via dosing pumps and don’t vary much at all, temp is controlled via Inkbird at 77.8-78.3 F, flow is controlled via dual opposing maxspect gyres set to random mode, so turnover is around 50-60x turnover at any given time. I bought a par meter and run 3 viparspectras, par is right around 280-325 at any point in the tank, running 10 hours per day.

I have slight specks if coralline developing in the past few days, and am running a Cheato fuge running on a 12 hour opposing light schedule. Tank is about 4 months old, could it just be lack of tank maturity or is there something I’m missing? Thanks!

 

[ninjamyst]

There is a lot that can't easily be tested. When people say tank needs to mature, it's often the biodiversity that plays a key role. Your best bet is to try and seed your tank with more mature rock or biomedia.

 

[coralfishreef]

My first tanks many years ago had ocean live rock. I waited the recommended time for curing live rock and then added fish and corals.

Those first tanks had T5 bulbs, basic powerheads, no sump, no automation, and used instant ocean salt. I had a swing arm hydrometer, performed water changes and water testing, but all in all I didn’t really know what I was doing. I had something similar to an inexpensive RO buddie without DI, water was topped off manually and somewhat randomly, and 2-part was also added manually.

Those tanks grew Acropora, Stylophora, Montipora, frogspawn, leathers, zoas, and anything else tossed into them which was mainly SPS since those were available. I didn’t have any strange 2-3 month RTN or STN. I did lose all zoas because of zoa spiders or some other pest from the live rock. All chromis vanished without a trace from what I suspect was another hitchhiker in the live rock. But, SPS grew, even with my basic equipment, inexperience, less than ideal stability, and sometimes dumb actions.

I believe that new tanks with sterile rocks have a much more difficult time with keeping SPS alive. In my experience, new tanks with dry rock and LED lights are not forgiving like a tank with mature rock and T5 lights. However, with all of this said, I am growing Acropora in a tank that is only 8 months old, bare bottom, dry rock, but seeded with a fistful of ceramic spheres from one my other older tanks.

 

[coralfishreef]

Having a hard time keeping my acropora happy, I’ve only lost one coral but I can notice some bleaching and lack of polyp extension and lack of growth on the others

At 4 months most people will probably have a hard time keeping Acropora alive or getting them to thrive.

What size tank? Gyres can put out a ton of flow which might be why you’re seeing less polyp extension. Less polyp extension or bleaching could be from the higher PAR. 285 - 325 is a lot of PAR in my opinion. I think the top rockwork in my SPS tank is around 225 to 240 PAR and the sand bed is around 150 PAR. That tank naturally runs ULN and usually runs at around 7 - 7.5 Alk. If Alk in that tank goes up to 9, some Acros will get burnt tips, and some Acros like red dragon may RTN. Other people may have different experiences but I have better results staying in the 7 - 7.5 Alk range.

 

[Drummerguydw]

At 4 months most people will probably have a hard time keeping Acropora alive or getting them to thrive.

What size tank? Gyres can put out a ton of flow which might be why you’re seeing less polyp extension. Less polyp extension or bleaching could be from the higher PAR. 285 - 325 is a lot of PAR in my opinion. I think the top rockwork in my SPS tank is around 225 to 240 PAR and the sand bed is around 150 PAR. That tank naturally runs ULN and usually runs at around 7 - 7.5 Alk. If Alk in that tank goes up to 9, some Acros will get burnt tips, and some Acros like red dragon may RTN. Other people may have different experiences but I have better results staying in the 7 - 7.5 Alk range.

It’s a 2x4x1 ft frag tank, I have dualmaxspect xf 280 gyres running at 80% on random mode, I will admit, I might have jumped the gun and added corals to early, I’m still pretty early on my ugly phase, and I have noticed diatoms and a tiny of of hair algae, not much since my cheato is keeping the nurtients in check and it’ll growing like crazy, but I do feed pretty heavy due to fish load.
I can try turning the gyres down a bit and seeing if that helps, the max flow on those is somewhere in the range of 6000 gph at 100%

 

[bar|none]

Less polyp extension or bleaching could be from the higher PAR. 285 - 325 is a lot of PAR in my opinion. I think the top rockwork in my SPS tank is around 225 to 240 PAR and the sand bed is around 150 PAR.

That's interesting. Most SPS tanks I've been following are running much higher par. For example, the discussion on PAR in this thread https://www.reef2reef.com/threads/farmertys-215-gallon-sps-tank.207702/page-372#post-9263906

 

[DesertReefT4r]

Did you use live rock or dry rock?

 

[Drummerguydw]

Did you use live rock or dry rock?

Dry rock with some new Brightwell media bricks

 

[DesertReefT4r]

Dry rock with some new Brightwell media bricks

With sterile dry rock it will simply take time for the tank to mature enough to keep sps like acros thriving. Can take a year or more in some cases. Best advice is to add some live rock from a mature established reef tank.